18 January 2008 It has been a few years since my last look at this code and I thought it time to update the source for Delphi 2007 SP3. I also made some changes for additional testing performed. I can be reached at zayin@pdq.net. Enjoy, Mark Everest Software LLC http://www.hmisys.com While every precaution has been taken in the preparation of this example/source code, Everest Software LLC and its employees assume no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained herein. 6 September, 2002 Small changes to allow Delphi 7.0 build. 5 July, 2001 Now compatible with Delphi 6.0 and 5.01. 14 March, 2001 I have run the server through the compliance test tool. I made the needed changes to pass the test. It now passes with just the warning(s) in data types. I have been told the test will be changed in the next version of the test tool. I used version 1.0.1070 of the Compliance Test Tool. One of the changes was to revert back to "flat" data storage. I have done a real hierarchical system and I did not have the time to implement it in this example. I also added the calls to prevent an error when terminating the example while clients are connected. I also incorporated the new headers Mike created. Enjoy. 31 January, 2000 Changed the browse method to "OPC_NS_HIERARCHIAL" which led to some other changes in data storage and collection. Added support for multiple clients. 7 October, 1999 I wrote this server code when I was learning COM and OPC. Errors in the code may be present and my interpretation/implementation of the specification for OPC Data Access 2.03, July 27, 1999 may also contain FUBARs. If you find any discrepancies or plain old errors please let me know what you found. This code is released with the purpose: give others a working example of how to write an OPC server using Delphi and OOP. It is intended to be an aid in learning how to write a server. It is not intended to be a template or a base for a product. If you wish to include any of this code in a product please contact Fire and Safety International, Systems, Inc. http://www.fsi-corp.com OOP is a great language and Delphi is a wonderful product for implementing OPC. Several people helped with an example or just an ear and a comment. I have never shaken hands with any of these guys. I say to them "Thank you". D.G. Somerton Astrit Shapiri John Romedahl Nickolas Robinson Roland Miezianko Mike Dillamore I tested the server with a program named Visual OPCTest Client. It is a great program. Roland Miezianko is the author. http://www.opctest.com is the web address. I can be reached at zayin@pdq.net. Enjoy the code, Mark R. Drake Fire and Safety International, Systems, Inc. Some other data: NT4 SP5 or later Delphi 5.01, 6.02 or Delphi 2007 SP3 You will need the OPC supplied DLLs: http://www.opcfoundation.org/ You will also need the Delphi conversions of the OPC interfaces: http://www.opcconnect.com/delphi.php While every precaution has been taken in the preparation of this example/source code, Fire and Safety International, Systems, Inc. and its employees assume no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained herein.